The Association of Early Postoperative Dysaesthesia with Thoracic Surgery

(1) Background: chronic pain following thoracic surgery is associated with dysaesthesia, which may be caused by intraoperative damage to intercostal nerves. This study’s primary aim was to compare, in the early postoperative period, the total area of dysaesthesia on the operated vs. the non-operated side of the thorax. Our secondary aims were to compare the total area of dysaesthesia between thoracotomy and video-assisted thoracic surgery (VATS) and to determine whether the area was associated with acute pain. (2) Methods: adult patients undergoing thoracic surgery underwent sensory examinations of the thorax using a monofilament and pin. Identified areas of hypoalgesia, hyperalgesia, allodynia and hypoaesthesia were marked on the skin, then copied onto tracing paper. Areas of dysaesthesia were estimated by weighing the cut-out, traced areas of paper and multiplying the weights by the paper’s known weight per area. Acute pain was assessed using a verbal rating score. (3) Results: the total area of dysaesthesia on the operated side [89 interquartile range (IQR) 8–167) cm2] was significantly greater than the non-operated side [0 (IQR 0–22) cm2] (p = 0.017), but not significantly different between thoracotomy [126 (IQR 16–392) cm2] and VATS [79 (IQR 4–161) cm2] (p = 1.0).The total area of dysaesthesia was not significantly correlated with acute pain severity after inspiration (r = 0.1, p = 1) or at rest (r = 0.1 p = 0.6). Conclusions: in the early postoperative period, thoracic surgery was associated with a larger total area of dysaesthesia on the operated compared to the non-operated side and the area was unrelated to acute pain, nor was it different between thoracotomy and VATS.